Front fork assembly for two wheel vehicles

ABSTRACT

A front fork assembly for two wheel vehicles such as motorcycles and bicycles which includes a pair of tubular trusses arranged in spaced parallel relation and joined by a handle bar on the upper end thereof. The truss members are joined adjacent their upper end by a triple clamp assembly for connecting the forks to the frame of the two wheel vehicle. A forwardly extending transversely pivoted wheel support member is pivotally mounted on the lower end of each of said forks and joined by an axle for supporting the front wheel. A sprung support is adjustably secured to the rear end of the wheel support member with the spring located within the tubular truss member.

United States Patent 1 1 Harman May 1, 1973 [54] FRONT FORK ASSEMBLY FORTWO FOREIGN PATENTS OR APPLICATIONS WHEEL VEHICLES 510,081 11 1920France ..280/277 I 2453 10 1922 S l d .280 27 [76] Inventor: John W.Harman, 501 Elefa Street, 0 wnzeran 7 Rosevinev Calif 95678 PrimaryExaminer-Kenneth H. Betts 22 Filed; 7 1971 Assistant Examiner.lohnMcCormack Appl. No.: 199,642

Attorney-Alexander B. Blair [5 7] ABSTRACT A front fork assembly for twowheel vehicles such as motorcycles and bicycles which includes a pair oftubular trusses arranged in spaced parallel relation and joined by ahandle bar on the upper end thereof. The truss members are joinedadjacent their upper end by a triple clamp assembly for connecting theforks to the frame of the two wheel vehicle. A forwardly extendingtransversely pivoted wheel support member is pivotally mounted on thelower end of each of said forks and joined by an axle for supporting thefront wheel. A sprung support is adjustably secured to the rear end ofthe wheel support member with the spring located within the tubulartruss member.

5 Claims, 4 Drawing Figures FRONT FORK ASSEMBLY FOR TWO WHEEL VEHICLESBACKGROUND OF THE INVENTION 1. Field of the Invention The inventionrelates to the front fork for supporting and steering a single frontwheel ofa vehicle.

2. Summary of the Invention The front fork includes a pair of spacedparallel tubular truss members connected by a handle bar at their upperend and by a triple clamp adjacent their upper end for connecting thefork to the frame of the vehicle. The lower end of the fork has a sprungwheel support pivotally mounted thereon and connected to a compressionspring through an adjustable linkage.

The primary object of the invention is to provide a front fork for avehicle which will permit the front wheel to be spaced considerablyahead of the frame and will spring mount the front wheel for a morecomfortable ride.

Other objects and advantages will become apparent in the followingspecification when considered in the light of the attached drawings.

FIG. 1 is a side elevation of the invention;

FIG. 2 is a top plan view of the invention;

FIG. 3 is a fragmentary front elevation of the triple clamp; and

FIG. 4 is an enlarged fragmentary longitudinal crosssection taken on theline 4-4 of FIGfl looking in the direction of the arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings indetail wherein like reference characters indicate like parts throughoutthe several figures the reference numeral 10 indicates generally a frontfork assembly for supporting the single front wheel of a vehicle such asa motorcycle or bicycle.

The front fork 10 includes a pair of elongate tubular members 11 securedto a handle bar 12 at their upper ends. A second tubular member 13 iswelded at 14 to the tubular member 11 near the handle bars 11 anddiverges rearwardly therefrom and then forwardly meeting the tubularmember 11 at its lower end which is welded at 15.

A plate 16 extends between and is welded to the tubular members 11, 13intermediate the upper and lower ends thereof and a second plate 17extends between and is welded to the tubular members II, 13 at a pointspaced above the plate 16. A shaft 18 extends between the plates I6 andis secured thereto by bolts I) which extend through the plates l6 andaxially into opposite ends 01 the shaft 18. A second shaft 20 extendsbetween the plates 17 and is secured thereto by bolts 21 which extendthrough the plates 17 and axially into the shaft 20. The shaft 22 ispositioned intermediate the spaced parallel tubular members 11 as can beseen in FIG. 2 and is mounted on a threaded shaft 23 on its lower endwhich is threaded through the shaft 18 1 axis and can be assembledthereto by removing the nut 27, bolts 21 and shaft 20 which are replacedto secure the fork 10 to the frame.

A pair of wheel support arms 28 are mounted intermediate their oppositeends on pivot bolts 2? which extend through the lower ends of thetubular members 11, 13 and are axially aligned. A shaft 30 rigidlyconnects the arms 28 to journal the front wheel of the vehicle thereonand to maintain the arms 28 in aligned relation.

A shaft 31 having its lower end threaded at 32 extends up into thetubular member 13 through a bore 33 formed therein. A spring seat 34 isrigidly mounted in the tubular member 13 to support a compression coilspring 35 in the tubular member 13. A washer 36 is positioned inengagement with the upper end of the spring 35 and a nut 37 threadedonto the upper end of the shaft 31 secures the washer 36 thereon. Amember 38 is threaded onto the threaded portion 32 of the shaft 31 andis retained thereon by ajamb nut 39. A bore 40 in the lower end of themember 38 receives a pivot 41 which extends through the rear end of thearm 28.

In the use and operation of the invention the fork 10 is mounted on theframe of a motorcycle or bicycle and a front wheel is journaled on theshaft 30. As the front wheel encounters uneven road surfaces it willcause the arms 28 to swing upwardly at their forward ends drawing theshafts 31 downwardly to compress the springs 35. By moving the member 38on the shaft 31 the tension on the spring 35 may be adjusted as desired.

The truss structure of the tubular members 11, 13 provides an extremelystrong fork support for the front wheel while maintaining a relative lowweight.

Having thus described the preferred embodiment of the invention itshould be understood that numerous structural modifications andadaptations may be resorted to without departing from the spirit of theinvention.

I claim:

1. A front fork assembly for vehicles of the type having a single frontwheel and a frame comprising a pair of spaced parallel tubular members,a second pair of spaced parallel tubular members rigidly secured to saidfirst pair of tubular members at the upper and lower ends thereof andspaced therefrom to form a pair of spaced parallel trusses, a shaft forpivotally mounting said fork assembly to said frame, means mounting saidshaft to said fork assembly intermediate the opposite sides thereof, apair of wheel support arms transversely pivotally mounted to the lowerend of said tubular members, means on said arms for journaling the frontwheel ofa vehicle at the front ends thereof, and means in the second ofsaid tubular members extending outwardly therefrom and connected to therear ends of said arms for spring mounting said arms for pivotalmovement on the lower ends of said tubular members.

2. A device as claimed in claim 1 wherein handle bars rigidly connectthe upper ends of said first named pair of tubular members.

3. A device as claimed in claim 1 wherein said first named shaft issupported on a pair of shafts extending between said tubular membersperpendicularly to said first named shaft.

4. A device as claimed in claim 1 wherein the means spring mounting saidarms is adjustable.

5. A device as claimed in claim 4 wherein the means spring mounting saidarms includes a pair of spaced parallel compression springs.

1. A front fork assembly for vehicles of the type having a single frontwheel and a frame comprising a pair of spaced parallel tubular members,a second pair of spaced parallel tubular members rigidly secured to saidfirst pair of tubular members at the upper and lower ends thereof andspaced therefrom to form a pair of spaced parallel trusses, a shaft forpivotally mounting said fork assembly to said frame, means mounting saidshaft to said fork assembly intermediate the opposite sides thereof, apair of wheel support arms transversely pivotally mounted to the lowerend of said tubular members, means on said arms for journaling the frontwheel of a vehicle at the front ends thereof, and means in the second ofsaid tubular members extending outwardly therefrom and connected to therear ends of said arms for spring mounting said arms for pivotalmovement on the lower ends of said tubular members.
 2. A device asclaimed in claim 1 wherein handle bars rigidly connect the upper ends ofsaid first named pair of tubular members.
 3. A device as claimed inclaim 1 wherein said first named shaft is supported on a pair of shaftsextending between said tubular members perpendicularly to said firstnamed shaft.
 4. A device as claimed in claim 1 wherein the means springmounting said arms is adjustable.
 5. A device as claimed in claim 4wherein the means spring mounting said arms includes a pair of spacedparallel compression springs.